Outline

Objective

Intraoperative computed tomography is a useful instrument for accurate image guided surgery as well for an intraoperative or a subsequent post operative control. In December 2001 the Advanced Workplace For Image Guided Surgery (AWIGS, Maquet, Rastatt, Germany) was for the first time nationally and internationally installed in the department of neurosurgery in Innsbruck.

Methods

The AWIGS (advanced workplace for image guided surgery) operation unit (Maquet, Rastatt, Germany) consists of an computer guided operation table which can be connected automatically to a fix installed tomographic scanner. The operation table consists of triple-section table top and a duplex column. Therefore no limitation in patients positioning exist in comparison to other operation tables. The table top is made of carbone and is radio translucent. From February 2002 until end of 2004 more than 2000 patients were treated in that operating room. The intraoperative CT was used more than 400 times where stereotactic operations are the main purpose. The HiSpeed X/I Z computed tomographic (CT) scanner (GE Medical Systems) is a single slice CT scanner fix installed in the operating room. The aperture of the gantry is 70 cm. The operating table as well as the docking procedure is completely computer controlled. The operating table is moved on floor rails. The operating and CT table are connected automatically. Special designed carbon head holders avoid problems concerning metal artefacts. After the CT scan the operating table is disconnected from the CT and the operating table is moved to the original position. The whole procedure (CT scan including table transfer) takes normally less than 20 minutes.

Results

The main purpose for the use of a intraoperative CT was a simplification of stereotactic imaging. Therefore it was used mainly for stereotactic operations. The time saving according to the original procedure is in minimum half an hour. Furthermore the patient needs not to be repositioned. Additionally subsequent postoperative controls are made before removing the stereotactic frame. Additionally the intraoperative CT was used for procedures of intracranial tumours, in spinal surgery and in vascular neurosurgery.

Conclusions

The intraoperative CT scanning is a powerful tool for planning as well as control of neurosurgical operations.